Short answers, pulled from the story.
The Trust Territory of the Pacific Islands was a United Nations trust territory in Micronesia administered by the United States from 1947 to 1994. It was designated a strategic area under the UN Charter, meaning only the Security Council could end the trusteeship. It encompassed six districts, nine spoken languages, and roughly 100,000 people scattered across a water area the size of the continental United States.
The United States seized the islands from Japan during the Pacific War, capturing them in 1944. The UN Security Council formalized US administration through Resolution 21 on the 18th of July 1947. Japan had previously administered the islands under a League of Nations mandate granted after World War I, having taken them from Germany during that conflict.
The Trust Territory ended in stages between 1986 and 1994. The Marshall Islands and the Federated States of Micronesia districts were terminated in October and November 1986, with the Security Council formally closing those trusteeships via Resolution 683 on the 22nd of December 1990. The trusteeship for Palau ended on the 25th of May 1994 under Resolution 956, with Palau becoming independent on the 1st of October 1994.
Four jurisdictions emerged: the Federated States of Micronesia, the Republic of the Marshall Islands, and Palau, which became sovereign states in free association with the United States; and the Northern Mariana Islands, which became a US commonwealth in political union with the United States.
The islands held an estimated 200,000 people in the late 19th century, but that figure fell to 100,000 by 1969 due to emigration, war, and disease. By the 1970 census, the population had partially recovered to 90,940. In 1969, fewer than 100 of the 2,141 Marshall, Mariana, and Caroline Islands were actually inhabited.
The Mariana Islands' Teacher Training School opened in Guam in 1947 and relocated to Chuuk in 1948, eventually becoming the Pacific Islands Central School in Pohnpei by 1959, now called Bailey Olter High School. The Community College of Micronesia began in Kolonia in 1969 and merged with the Micronesian Occupational College in Koror to form the College of Micronesia-FSM in 1976.